Dry ice conversion unit



April 25, 1933. E O BENNETT 1,905,885

DRY ICE CONVERSION UNIT Filed Oct. 31, 1931 2 Sheets-Sheet 1 INVENTOR. EdW/fl 0. 56/7/7677 ATTORNEY.

April 25, 1933.

E. O. BENNETT DRY ICE CONVERSION UNIT 2 Sheets-Sheet 2 Filed Oct. 31, 1951 INVENTOR 1 ATTORN beused as 20 of a large block of water-ice.

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OKLAHOMA conronanon or ma ICE oonvimsron mum PATENT oFFic Application fled October :11, 1931., Serial 10.372345.

7 My invention relates to a dry ice conversion unit and more particularly to a container for dry. ice (solid CO so that. it may a refrigerant in an ordinary W81 ter-ice box. e

'- Inasmuch as the temperatures produced by dry ice are extremely low, dry ice cannot be used in ordinary ice boxes as a substitute for water-ice, because the comestibles ,in the ice box will become frozen sohd. The

temperature of dry ice is about 110 below zero F. a A

One pound of dry ice willproduce the same refrigerating effect as 14 pounds of water-ice. That is, dry ice is aboutfourteen times as eflicient as water-ice, asa re-' frigerant. Accordingly, it is obvious that a small block of dry ice will be the equivalent One object of my invention is to provide a unit which will enable dry ice to be used as are'frigerant in the ordinary water-ice,

box. v Another object of my invention is improvide' a unit wherebydry ice-may be used withgut freezing of the comestibles in the me x.

' vlde a refrigerating efiect control so that the temperature in the-ice-box may be controlled. a

7 Still another object of my invention is to provide means for water into cubes of water-ice so water-ice maybe available for cooling drinks and. other purposes. Astill further object of my invention is to provide a vent which will preclude pressure being built u during the sublimation process of the C a state, due to. the absorption of heat. by thedryice. j

Figure 1 shows a front elevationof an ice box equipped with one-embodiment of. my nvention. p v Figure 2 shows asection'taken on Figure 1 along the'line 2 2.

re 3 shows a sectional view of a device embodying my Invention, showing control means for governing theytemperat re of therefrigerator.

, of openings A further object of my invention is to pro-.

partition' '3 divides the container upper chamber 4 provided with a door 5 of a'bloclc of dryioe 6.

solidjto the gaseous state. from the solid to the be;

- are provided with shutters Figure4 is line 4-4 ofFlgure 3 sectional view taken'on the ASSIGIIDB TO CONTINENTAL 'OIL Figure 5 is a perspective view or the conversion unit,- showmg the control Figure 6 is a perspective view showing another type of control means.

In general my invention contemplates a heat insulated unit suitably partitioned to provide an upper chamber for the reception of a (gantity of dry ice. Belowthe dry ice cham r are positioned a plurality of trays for the reception of water to be frozen into watereice. The upper and lower surfaces of the unit are provided with a plurality through which air cireulation These holes are provided with any suitably constructed control means so that the area through which air circulation takesplace niay be varied. Means are provided forcontrolling this area throughthe cgiiltrolmeans either manually or c y- L More particularly referring now to -the drawings; the dry ice container Iis mounted in any suitable fashion in a'fnormal ice chamber of a walls of the container 1 are made suitable heat insulation construction. A into an takes place.

lower chamber of the container 7 is provided with two water-ice trays 8. A vvent 9 precludes the building up of pressure due to the sublimation of the dryice from the 1 The vent 9 may provided with a valve arrangement 10 which may be hingedly mounted so that it will open upon the slightest pressure. A suitable baflle- 13 may be provided at the interior orifice of vent 9 to prevent. the

drawing in of any warm air due to .the circulation .of the cooled air the .box. Aseri es' of openings 11 are provided in the upper wall ofimy containen. The lower walls ofmy series of openings 12'.

automati-' container are provided with a These openings12' other suitable 75 common water-ice box'2. The

of any 7 ice is placed in the upper rotate rod20 which carries control means to vary the amount of opening. The shutter or shutters may be manually controlled or thermostatically controlled by any suitable mechanical or electrical thermostatic device. The operating means for the cooling control is diagrammatically shown at 12 and may be positioned in any suitable location.

In operation my unit is installed in an ordinary water-ice box and a piece of dry chamber of my unit. The arrows in Figure 1 indicate the circulation through my ice box. -As the air is cooled, it becomes more dense and passes downwardly through the lower holes 12 and over the comestibles in the ice box, cooling them. Having absorbed some of the heat from the comestibles present, the air will become lighter andrise and pass downwardly through the refrigerant container. obvious that the size of the openings or the number of openings will govern the cooling effect and accordingly the temperature within'the ice box.

Water-ice may be frozen in the trays and thus can be used for beverage and other household purposes. The vent will prevent the building up of any undesirable pressure. There is no necessity of fitting drains as is the case in an ordinary ice box. The temperature control will prevent undue dissipation of the dry ice and it will last a surprising length of time. There are' no moving parts to get out of order. No defrosting, as is the case with mechanical refrigerators is necessary. The dry ice need only be replenished at more or less infrequent intervals depending upon how much demand is made upon the refrigerant.

The switch member 12, when rotated. will a worm 21. Suitably mounted within the refrigerator upon supports 22 and 23 is a rod 24 which carries a segment of a gear 25. The segment 25 is keyed to rod 24. Also keyed to rod 24 are levers 26 and 27 provided with slots 28 and 29 which engage pintles 30 and 31'. The pintlesare mounted in shutter members 32 and 33 which are disposed to slide in guide members 34. The shutter members 32 are provided with openings 35 which are spaced in the same relationship as the openings 11 and 12. As the shaft 20 is rotated, the arran'gement will reciprocate the shutters 32 to positions which vary the effective area through which the circulation of refrigerant gas takes place. The linkage in Figure 6 is a modification which may be employed, in which shaft 20 carries a lever 40 which is connected to links 42 and 43 by means of ilinks 41. Bell crank, levers 44 and 45 are mounted upon suitable brackets 46 and 47 The bell crank levers have slotted ends 48 and '49 which engage .pintles 30 and' 31' of the shutter members 32 and 33 as in the previous modification. 1

It is obvious that I have provided a means for employing dry ice which will enable it to be used as a refrigerant having substantially all of the advantages of the mechani cal refrigerator and none of its disadvan tages. Then, too, it is obvious that all of the advantages of a water-ice box are retained with none of its disadvantages present. With dry ice there is none of the undesirable dehydration of the comestibles which takes place in a mechanical refrigerator.

Though I have described .a unit which may be used for the conversion of a water-ice box, it is manifest that my invention may be embodied in an ice box during manufacture, where designed especially for dry ice alone.

With the conversion .unit, however, it is a simple matter in the event that a supply of dry ice becomes inaccessible that the ice box can be again used as an ordinary waterice box without great difliculty.

It is to be understood that my invention is not to be limited to the specific details shown and described except in so far as expressed in my claims.

I claim as my invention:

1. A conversion unit adaptedto modify a water-ice box for use with dry ice compris ing, a container having heat insulated walls, a perforated partition in said container dividing it into upper and lower chambers, said partition being adapted to support a piece of dry ice, a tray adapted to contain water to be frozen slidably positioned below said partition within said lower chamber, a plurality of openings in said container adapted to permit a circulation of ice box air through said container, and means to vary the effective area of said openings.

2. A conversion unit adapted to modify a water-ice box for use with dry ice comprising, a container having heat insulated walls, a perforated partition in said container dividing it into upper and lower chambers, said partition being adapted to support a piece of dry ice, a tray adapted to contain water to be frozen slidably positioned below said partition withinsaid lower chamber, a plurality of openings in said container adapted to permit a circulation of ice box air through said container, means to vary the effective area of said openings, and means to control said means.

3. An ice box including the combination ofa container having heat insulated walls, a perforated partition in' said container dividingit into upper and lower chambers, said partition being adapted to support a piece of dry ice, a tray adapted to contain water to be frozen slidably positioned below said partition within said lower chamber, a plurality of openings in J said container adapted to permit a circulation of ice box air through said container, and means to vary the-effective area of said openings.

4. An ice box including the combination of a container having heat insulated walls, a perforated partition in said container dividing it into upper and lower chambers, said partition being adapted-to support a piece of dry ice, a tray adapted to contain water to be frozen slidably positioned below said partition within said lower chamber, a plurality of openingsin said container adapted to permit a circulation of ice box air through said container, means to vary the effective area of said openings, and means to control said means.

In testimony whereof'I afiix my signature.

/ EDWIN O. BENNETT. 

